1 /*
2 * fs/cifs/smb2file.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002, 2011
5 * Author(s): Steve French (sfrench@us.ibm.com),
6 * Pavel Shilovsky ((pshilovsky@samba.org) 2012
7 *
8 * This library is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License as published
10 * by the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 * the GNU Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22 #include <linux/fs.h>
23 #include <linux/stat.h>
24 #include <linux/slab.h>
25 #include <linux/pagemap.h>
26 #include <asm/div64.h>
27 #include "cifsfs.h"
28 #include "cifspdu.h"
29 #include "cifsglob.h"
30 #include "cifsproto.h"
31 #include "cifs_debug.h"
32 #include "cifs_fs_sb.h"
33 #include "cifs_unicode.h"
34 #include "fscache.h"
35 #include "smb2proto.h"
36
37 int
smb2_open_file(const unsigned int xid,struct cifs_open_parms * oparms,__u32 * oplock,FILE_ALL_INFO * buf)38 smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms,
39 __u32 *oplock, FILE_ALL_INFO *buf)
40 {
41 int rc;
42 __le16 *smb2_path;
43 struct smb2_file_all_info *smb2_data = NULL;
44 __u8 smb2_oplock[17];
45 struct cifs_fid *fid = oparms->fid;
46 struct network_resiliency_req nr_ioctl_req;
47
48 smb2_path = cifs_convert_path_to_utf16(oparms->path, oparms->cifs_sb);
49 if (smb2_path == NULL) {
50 rc = -ENOMEM;
51 goto out;
52 }
53
54 smb2_data = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
55 GFP_KERNEL);
56 if (smb2_data == NULL) {
57 rc = -ENOMEM;
58 goto out;
59 }
60
61 oparms->desired_access |= FILE_READ_ATTRIBUTES;
62 *smb2_oplock = SMB2_OPLOCK_LEVEL_BATCH;
63
64 if (oparms->tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING)
65 memcpy(smb2_oplock + 1, fid->lease_key, SMB2_LEASE_KEY_SIZE);
66
67 rc = SMB2_open(xid, oparms, smb2_path, smb2_oplock, smb2_data, NULL);
68 if (rc)
69 goto out;
70
71
72 if (oparms->tcon->use_resilient) {
73 nr_ioctl_req.Timeout = 0; /* use server default (120 seconds) */
74 nr_ioctl_req.Reserved = 0;
75 rc = SMB2_ioctl(xid, oparms->tcon, fid->persistent_fid,
76 fid->volatile_fid, FSCTL_LMR_REQUEST_RESILIENCY, true,
77 (char *)&nr_ioctl_req, sizeof(nr_ioctl_req),
78 NULL, NULL /* no return info */);
79 if (rc == -EOPNOTSUPP) {
80 cifs_dbg(VFS,
81 "resiliency not supported by server, disabling\n");
82 oparms->tcon->use_resilient = false;
83 } else if (rc)
84 cifs_dbg(FYI, "error %d setting resiliency\n", rc);
85
86 rc = 0;
87 }
88
89 if (buf) {
90 /* open response does not have IndexNumber field - get it */
91 rc = SMB2_get_srv_num(xid, oparms->tcon, fid->persistent_fid,
92 fid->volatile_fid,
93 &smb2_data->IndexNumber);
94 if (rc) {
95 /* let get_inode_info disable server inode numbers */
96 smb2_data->IndexNumber = 0;
97 rc = 0;
98 }
99 move_smb2_info_to_cifs(buf, smb2_data);
100 }
101
102 *oplock = *smb2_oplock;
103 out:
104 kfree(smb2_data);
105 kfree(smb2_path);
106 return rc;
107 }
108
109 int
smb2_unlock_range(struct cifsFileInfo * cfile,struct file_lock * flock,const unsigned int xid)110 smb2_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
111 const unsigned int xid)
112 {
113 int rc = 0, stored_rc;
114 unsigned int max_num, num = 0, max_buf;
115 struct smb2_lock_element *buf, *cur;
116 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
117 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
118 struct cifsLockInfo *li, *tmp;
119 __u64 length = 1 + flock->fl_end - flock->fl_start;
120 struct list_head tmp_llist;
121
122 INIT_LIST_HEAD(&tmp_llist);
123
124 /*
125 * Accessing maxBuf is racy with cifs_reconnect - need to store value
126 * and check it before using.
127 */
128 max_buf = tcon->ses->server->maxBuf;
129 if (max_buf < sizeof(struct smb2_lock_element))
130 return -EINVAL;
131
132 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
133 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
134 max_num = max_buf / sizeof(struct smb2_lock_element);
135 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
136 if (!buf)
137 return -ENOMEM;
138
139 cur = buf;
140
141 cifs_down_write(&cinode->lock_sem);
142 list_for_each_entry_safe(li, tmp, &cfile->llist->locks, llist) {
143 if (flock->fl_start > li->offset ||
144 (flock->fl_start + length) <
145 (li->offset + li->length))
146 continue;
147 if (current->tgid != li->pid)
148 continue;
149 if (cinode->can_cache_brlcks) {
150 /*
151 * We can cache brlock requests - simply remove a lock
152 * from the file's list.
153 */
154 list_del(&li->llist);
155 cifs_del_lock_waiters(li);
156 kfree(li);
157 continue;
158 }
159 cur->Length = cpu_to_le64(li->length);
160 cur->Offset = cpu_to_le64(li->offset);
161 cur->Flags = cpu_to_le32(SMB2_LOCKFLAG_UNLOCK);
162 /*
163 * We need to save a lock here to let us add it again to the
164 * file's list if the unlock range request fails on the server.
165 */
166 list_move(&li->llist, &tmp_llist);
167 if (++num == max_num) {
168 stored_rc = smb2_lockv(xid, tcon,
169 cfile->fid.persistent_fid,
170 cfile->fid.volatile_fid,
171 current->tgid, num, buf);
172 if (stored_rc) {
173 /*
174 * We failed on the unlock range request - add
175 * all locks from the tmp list to the head of
176 * the file's list.
177 */
178 cifs_move_llist(&tmp_llist,
179 &cfile->llist->locks);
180 rc = stored_rc;
181 } else
182 /*
183 * The unlock range request succeed - free the
184 * tmp list.
185 */
186 cifs_free_llist(&tmp_llist);
187 cur = buf;
188 num = 0;
189 } else
190 cur++;
191 }
192 if (num) {
193 stored_rc = smb2_lockv(xid, tcon, cfile->fid.persistent_fid,
194 cfile->fid.volatile_fid, current->tgid,
195 num, buf);
196 if (stored_rc) {
197 cifs_move_llist(&tmp_llist, &cfile->llist->locks);
198 rc = stored_rc;
199 } else
200 cifs_free_llist(&tmp_llist);
201 }
202 up_write(&cinode->lock_sem);
203
204 kfree(buf);
205 return rc;
206 }
207
208 static int
smb2_push_mand_fdlocks(struct cifs_fid_locks * fdlocks,const unsigned int xid,struct smb2_lock_element * buf,unsigned int max_num)209 smb2_push_mand_fdlocks(struct cifs_fid_locks *fdlocks, const unsigned int xid,
210 struct smb2_lock_element *buf, unsigned int max_num)
211 {
212 int rc = 0, stored_rc;
213 struct cifsFileInfo *cfile = fdlocks->cfile;
214 struct cifsLockInfo *li;
215 unsigned int num = 0;
216 struct smb2_lock_element *cur = buf;
217 struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
218
219 list_for_each_entry(li, &fdlocks->locks, llist) {
220 cur->Length = cpu_to_le64(li->length);
221 cur->Offset = cpu_to_le64(li->offset);
222 cur->Flags = cpu_to_le32(li->type |
223 SMB2_LOCKFLAG_FAIL_IMMEDIATELY);
224 if (++num == max_num) {
225 stored_rc = smb2_lockv(xid, tcon,
226 cfile->fid.persistent_fid,
227 cfile->fid.volatile_fid,
228 current->tgid, num, buf);
229 if (stored_rc)
230 rc = stored_rc;
231 cur = buf;
232 num = 0;
233 } else
234 cur++;
235 }
236 if (num) {
237 stored_rc = smb2_lockv(xid, tcon,
238 cfile->fid.persistent_fid,
239 cfile->fid.volatile_fid,
240 current->tgid, num, buf);
241 if (stored_rc)
242 rc = stored_rc;
243 }
244
245 return rc;
246 }
247
248 int
smb2_push_mandatory_locks(struct cifsFileInfo * cfile)249 smb2_push_mandatory_locks(struct cifsFileInfo *cfile)
250 {
251 int rc = 0, stored_rc;
252 unsigned int xid;
253 unsigned int max_num, max_buf;
254 struct smb2_lock_element *buf;
255 struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
256 struct cifs_fid_locks *fdlocks;
257
258 xid = get_xid();
259
260 /*
261 * Accessing maxBuf is racy with cifs_reconnect - need to store value
262 * and check it for zero before using.
263 */
264 max_buf = tlink_tcon(cfile->tlink)->ses->server->maxBuf;
265 if (max_buf < sizeof(struct smb2_lock_element)) {
266 free_xid(xid);
267 return -EINVAL;
268 }
269
270 BUILD_BUG_ON(sizeof(struct smb2_lock_element) > PAGE_SIZE);
271 max_buf = min_t(unsigned int, max_buf, PAGE_SIZE);
272 max_num = max_buf / sizeof(struct smb2_lock_element);
273 buf = kcalloc(max_num, sizeof(struct smb2_lock_element), GFP_KERNEL);
274 if (!buf) {
275 free_xid(xid);
276 return -ENOMEM;
277 }
278
279 list_for_each_entry(fdlocks, &cinode->llist, llist) {
280 stored_rc = smb2_push_mand_fdlocks(fdlocks, xid, buf, max_num);
281 if (stored_rc)
282 rc = stored_rc;
283 }
284
285 kfree(buf);
286 free_xid(xid);
287 return rc;
288 }
289